In recent years, light-emitting devices and display devices are expected to be applied to a variety of uses and required to be diversified.
Increase in the size of display devices has been required for uses in a television device for home use (also referred to as a TV or a television receiver), digital signage (Digital Signage: electronic signboard), PID (a public information display), and the like, for example. A larger display region of a display device can provide more information at a time. In addition, a larger display region is likely to attract more attention of people, so that the effectiveness of the advertisement is expected to be increased, for example.
In addition, for uses in mobile devices, the increase in the size of a display device has been required. Increasing the amount of information to be displayed at a time by making a display region large to improve browsability has been considered. In contrast, for uses in mobile devices, reduction in the size of a display device has also been required to increase the portability.
Light-emitting elements (also referred to as EL elements) utilizing electroluminescence (electroluminescence, hereinafter, also referred to as EL) phenomenon have features such as ease of thinning and lightening, high-speed response to an input signal, and driving with a direct-current low voltage power source; thus, application to display devices has been considered.
For example, Patent Document 1 discloses a flexible light-emitting device to which an organic EL element is applied.